Quote:

Went to the track the 1st time with my my Pro Systems 750 Holley.

Currently its running a 50cc front shooter and 30cc rear shooter - both new diaphrams.

The car hooked fine..but my 60ft was still about 1/10th under where I think it should be...(Best was 1.84)

It feels "soggy" at launch..and there was no difference between a launch at 800rpm and at 2500



So here's my questions -

What is the recommended set up for dual pump shooters?

- should they be the same size..or should the primary be smaller than the sec?

What effect does it have swapping the small one and the big one from primary side to secondary side?

Can I run a 30cc diaphragm on a 50cc cam? What effect would this have?

Please bear with me - I'm not seeking "tuning" advice for this motor - its not far off being jetted correctly....but I don't understand how the twin pump shooter configuration is supposed to be set up.....





I'm not a fan of ProSystems...that said I think the larger pump should be on the secondary side as that's the side that most times has to cover the "hole" made by going to WOT.
I start my holleys with Blue cams, and then go up on the squirters until there is no hesitation or your 60ft. is at it's best.
With 4 corner idle, you need to make sure the secondaries are cracked open some so there is a signal to the idle circuit and the Main circuit once it starts to move.
Also, make sure the idle mixture screws aren't set too lean...they will have an affect on going to WOT and the "hole" that's created by that sudden change in depression.
Brian

Brian Hafliger